Charles Samuel Watson, known as Sam, from Henstead, near Kessingland in Suffolk, went missing after attending a stag do in Great Yarmouth.

He was last seen in the early hours of Easter Monday, April 9, when he split up from his friends after leaving Caesar’s Bar in Marine Parade.

He had intended to stay with a friend, Roger Hurren, and he had been offered a lift back, but the inquest heard that he changed his mind and decided to drive home.

He texted Mr Hurren from his car at 3.15am to say that he had found somewhere else to stay. Less than a minute later his mobile phone came off the network, which was probably the time when he unintentionally drove the car into the water in the River Waveney near to St Olaves, the inquest heard.

Mr Watson’s body was recovered from the silver VW Golf, and he was pronounced dead on Friday, April 13.

Yesterday’s Norwich inquest heard that Mr Watson, who was a contracts manager, had 234mg of alcohol per 100ml of blood, while the legal limit is 80mg.

The inquest heard that the amount of alcohol in his system would have impaired his driving and prevented his possible escape from the vehicle when it went into the water.

Norfolk coroner William Armstrong recorded a verdict of accidental death from drowning after driving a vehicle into a river. He said it would remain a mystery why Mr Watson split from his friends and where he went before driving home.

Afterwards, Mr Watson’s family said in a statement: “We have been absolutely overwhelmed by the support we have received.

“We are still mourning the tragic death of a wonderful son and brother. We now hope that we can move on and find some formal closure.”